Free tool · strength
1RM and progression calculator
Estimate your one-rep max from a normal working set, read off matching training loads and plan the next weeks with linear progression and a deload.
- Epley & Brzycki
- NSCA percentage table
- Progression plan with deload
- Uses sets from your log
- formulas
- 2
- steps in the percentage table
- 13
- weeks of progression
- 4–8
Your best set
Clean form, close to failure. Most accurate at 2–10 reps.
Round to
Estimated 1RM
91.5kg
Epley 93.5 kg · Brzycki 90 kg
Percentage table
| % 1RM | Load | Reps possible |
|---|---|---|
| 100 % | 92.5 kg | 1 |
| 95 % | 87.5 kg | 2 |
| 93 % | 85 kg | 3 |
| 90 % | 82.5 kg | 4 |
| 87 % | 80 kg | 5 |
| 85 % | 77.5 kg | 6 |
| 83 % | 75 kg | 7 |
| 80 % | 72.5 kg | 8 |
| 77 % | 70 kg | 9 |
| 75 % | 70 kg | 10 |
| 70 % | 65 kg | 11 |
| 67 % | 62.5 kg | 12 |
| 65 % | 60 kg | 15 |
Progression planner
Linear progression with a deload in the final week. If a week doesn't go cleanly: hold the weight instead of adding.
Target reps
Sets
Weeks
Increase per week
| Week | Load | % 1RM | Sets × reps |
|---|---|---|---|
| 1 | 70 kg | 76 % | 3 × 5 |
| 2 | 72.5 kg | 79 % | 3 × 5 |
| 3 | 75 kg | 82 % | 3 × 5 |
| 4 | 77.5 kg | 85 % | 3 × 5 |
| 5 | 80 kg | 87 % | 3 × 5 |
| 6Deload | 72.5 kg | 79 % | 2 × 5 |
Estimates for trained people without injuries. True max attempts only with safety (spotter, safety bars) and a proper warm-up. Everything runs only in your browser – your log is only read.
Method
How the 1RM calculator works
- 1
Two formulas
Epley: weight × (1 + reps/30). Brzycki: weight × 36 / (37 − reps). The calculator shows the average of both.
- 2
Accuracy
Up to about 10 reps the estimates are usable; beyond that the error grows clearly. Heavy sets of 2–6 reps are most accurate.
- 3
Percentage table
The NSCA table maps each percentage of 1RM to a typical number of reps – that's how you find your working weight.
- 4
Progression
A small increase each week, capped at what's realistic for the target reps, and a lighter deload week at the end.
Sources
- LeSuer et al. 1997: Accuracy of prediction equations for estimating 1-RM (J Strength Cond Res 11:211–213), cited in Eston & Evans 2009
- Brzycki 1993: Strength testing – predicting a one-rep max from reps-to-fatigue
- Haff & Triplett (eds.) 2016: NSCA – Essentials of Strength Training and Conditioning, 4th ed.
1RM FAQ
What is a 1RM?
The one-rep max is the weight you can lift exactly once with clean form in an exercise. It's the reference for training loads in percent.
How accurate is the estimate?
At 2–6 reps it's usually close to the true value; above 10 reps it gets clearly less accurate. Formulas differ by exercise and training status.
Do I have to test my max?
No. For planning, an estimate from a heavy set is enough. True max attempts only when well warmed up and with safety.
How fast should I progress?
Beginners can often add weight weekly, advanced lifters more slowly. If a week doesn't go cleanly, hold the weight instead of adding more.